A remarkably speedy and accurate testing tool available today allows scientists
and health officials to hunt down the exact pathogen strain out of hundreds that
could be contaminating an environment and affecting human health.
Known as real-time PCR (polymerase chain reaction), the technology takes the
guesswork out of environmental forensic investigation. It does so by not only
naming the spore, but also its exact variant and concentration within a business
or residence, thereby pointing the way to the kind of remediation that might be
needed to protect people from further exposure to these largely invisible
contaminants.
At Clean Air Inspections (a unit of Estero, Fl.-based Chiodo Companies, a
conglomerate with interests in environmental health and safety) we think the
value the technology offers is akin to the confidence physicians gained when Xrays vastly improved their diagnostic skills.
We now have a valuable tool that can tell with 99.99% certainty the airborne or
surface pathogen infecting an environment, something that spore trap analysis,
which most investigators use, does not do. Our environmental forensics team of
11 meets with clients nationally to examine the causes of potential contamination and to collect samples for DNA sequencing. The lab work is preformed at the Chiodo Companies’ Tennessee facilities where real-time PCR units rapidly multiply fragments of DNA to identify the strain of pathogen and its viral load, producing results in as few of six hours.
Spore trap analysis, by contrast, gives investigators and the people who hire
them, a rough picture of the kind of airborne pathogen that might be infecting an
environment. The technique does not involve creating a culture or running a
sample through a machine that amplifies genetic material to identify its DNA or
RNA sequences. Rather, the method uses an air pump that allows air to pass
through an opening, and in the process, captures spores onto a sticky surface.
Investigators then count the number of trapped spores to arrive at an estimate of its concentration within a facility. And, they identify the species of pathogen, but are unable to tell which of the one of tens or hundreds of strains within the
species is the culprit contaminant. The method boasts an accuracy rate of about
50%.
As one of the last century’s most significant bio-molecular developments. PCR
has moved from pathology and biopharmaceutical labs to become a valued tool
for industrial hygienists. It has opened up a new world for environmental
investigators who now can conclude with scientific validity and in rapid fashion
the organisms that cause humans to become ill.
Of particular importance is the small segment of the population that is especially
sensitive to airborne pathogens. They may have a suppressed immune system,
an inherent sensitivity to mold, or could be asthmatic and cannot fend off air or
surface pathogens. As a result, these people have a tendency to first grow ill
and then very ill, because tests have been unable to pinpoint the exact infectious
spore that gives rise to their condition.
Some studies have shown that about one-third of chronic sinusitis cases cannot
be treated with antibiotics because the root cause is an exposure to a fungus,
and must therefore be attacked with fungal medicine. Here’s an example of
where the Chiodo Companies’ Clean Air Unit’s expertise grows especially
significant. Commercial office buildings, health care facilities, day care centers,
school districts and homeowners, look to the firm to detect through its
sophisticated lab instruments the hidden, yet insidious, pathogen that could be
lurking within their structures.
A spore trap analysis probably would suffice in cases where mold damage is
extensive. A case in point would be the aftermath of Hurricane Katrina, when
homes and buildings thrashed throughout the Gulf Coast, saw high
concentrations of mold appear suddenly. There, fungal growth was obvious to
any passer-by, and the use of the simpler technique to confirm the nature of a
mold could be justified.
Today’s improvements in speed, sample size, sample handling and real-time
applications breathe new vigor into the revolution created by PCR technology.
Consider a common indoor pathogen in Florida, asperguillus, which boasts about
185 different strains, although only two to three of these are infectious. A spore
trap analysis will not reveal whether the strain that exists within a building is
infectious or not. And, most environmental inspectors will end their reports
noting that a form of asperguillus has been discovered.
But, the Chiodo Companies’ state-of-the-art lab takes matters a step farther,
offering rapidly generated and specific information that scientifically validates
collected data. We inform a client about the exact strain of an airborne
contaminant that has infected his structure.
At the outset, even before a stick of furniture is swabbed or a speck of dust
collected, our team applies a form of deductive thinking to address the origin and cause of a problem. We begin by questioning a building’s occupants of the human ailments they suspect rise from within the structure, be it a suspicion that
points to an air-conditioning and heating vent or lack of air flow, for example.
Clean Air Inspections then forms a strategy to determine which tests need to be
taken and where. Samples obtained from a site are carefully noted in a chain of
custody and transported to the Chiodo Companies’ lab for analysis. The lab’s real-time PCR units generate results within hours, and we prepare a report in “plain English”. In it, we might conclude that occupants may experience physical
symptoms because of the existence of a concentration of particular pathogens.
We then address the treatment protocol to eliminate a recurrence of an infectious
spore.
The firm does not implement improvement measures. To do so would be a
conflict of interest.
There’s a clear-cut value to a real-time PCR analysis over a spore trap analysis.
The biggest benefit is that we can now show a client how much remediation he
needs to do in order to fix an airborne problem. Costing marginally more than a
spore trap analysis, the real-time PCR method provides an unequivocal answer
as to which pathogen is compromising human health, allowing you to spend no
more than you need to eliminate an infectious spore from your environment.
